Device for automatically smoothing in the rear strip in manufacturing rubber boots or other shoes



5 l H a e 3 mm 3 v n A S $2 P" 1960 F. SLEZAK ETAL DEVICE FORAUTOMATICALLY SMOOTHING IN THE REAR STRIP IN MANUFACTURING RUBBER BOOTFiled July 18, 1958 INVENTORS. Frargfi's'ek J/eza'lr By A9018 GajdgifekJosef H02;

Aprll 26, 1960 F. sLEzAK EIAL 2,933,745

DEVICE FOR AUTOMATICALLY SMOOTHING IN THE REAR STRIP IN MANUFACTURINGRUBBER BOOTS OR OTHER SHOES Filed July 18, 1958 2 Sheets-Sheet 2 Hr wakW m m ak w V wd w. K Wu wm M J6 0.5!! M2 AJ United States Patent CDEVICE FOR AUTOMATICALLY SMOOTHING IN THE REAR STRIP IN MANUFACTURINGRUB-' BER BOOTS OR OTHER SHOES 7 Claims. (01. 12-533 The presentinvention relates generally to the manufacture of rubber boots, and moreparticularly is directed to an improved device-for rolling the rubberstrip which is laid over the rear seam of each rubber boot while thelatteris carried by a conveyor.

Heretofore, the rolling of the strip laid over the rear seam of a rubberboot has been carried out with a metal roller having a cylindricalsurface and which is manually pressed against the curved surface of theleg portion of the boot being produced while the roller is moved alongthe strip several times in both directions. The failure of the operatorto maintain a uniform manual pressure of the cylindrical roller againstthe strip during the repeated movement of the roller along the stripfrequently causes inadequate adherence of the strip to the leg portionof the boot and thereby results in an increase in thenumber of secondsor rejects. Further, the need to continuously apply manual pressure forurging the roller against the leg 2,933,745 Patented Apr. 26, 1960 2 Theabove, and other objects, features and advantages of the invention, willbe apparent in the following detailed description of an illustrativeembodiment thereof, which is to be read in connection with theaccompanying drawings forming a part hereof, and wherein:

Fig. 1 is a perspective view of the device embodying the invention; Fig.2 is a fragmentary perspective view of a portion another portion of thedevice shown in Fig. 1.

Referring to the drawings in detail, and initially to Fig. 1 thereof, itwill be seen that the device embodying the present invention isassociated with a conveyor D carrying spaced apart metal lasts K uponwhich rubber boots are to be manufactured. The lasts K are arranged onthe conveyor D so that, at the location of the smoothing or rollingdevice embodying the invention, each last K will be disposed with theleg portion of the related boot extending'transversely relative to thedirection of movement of the conveyor, and with the toe portion of theboot directed downwardly. The rolling or smoothingdevice embodying theinvention includes an upright 28 disposed at the back of the conveyor Dand fixedly secured to the frame R of the conveyor. The upper end ofupright 28 is formed a with a longitudinally split tubular portion 47having its portion of the boot results in considerable muscular fatigue,frequent blistering of the workers hands and overstraining of the wrist.Another disadvantage of the described existing procedure consists in thenecessity of manually aligning and straightening the strip relative tothe rear seam as the'strip is laid against the rear seam of the boot,and these manual operations increase'the time required for theattachment of the strip to the boot with consequent losses in the dailyproduction output.

Accordingly, it is an object of the present invention to provide adevice which automatically smooths or rolls the rearstrip laid over theseam at the back of the rubber boot, and which operates in synchronisinwith the intermittent movement of the conveyor carrying the boots beingmanufactured, thereby to eliminate the manually performed operations ofthe above described existing procedure.

In accordance with an aspect of the invention, the device for smoothingor rolling the strip laid over the seam at the rear of each rubber bootcarried by the conveyor includes a support structure extending above theconveyor transversely relative to the direction of movement of thelatter and carried by an upright which is rigiddly joined to the frameof the conveyor, with such support structure including guide rodscarrying a movable assembly which is actuated by a fluid pressureoperated device and which includes a contoured roller movable along thestrip laid over the rear seam of a boot in response to operation of thefluid pressure operated device while being resiliently 'urged againstthe strip.

Further, in accordance with the invention, the operationof the fluidpressure operated device causing the movement of the contoured rolleralong the strip laid 4 over the rear seam of the boot is automaticallysynchronized with the intermittent'movement of the conveyor so that the.need for intervention by the worker or operator is greatly minimized inorder to achieve a substantially axis extending transversely relative tothe direction of movement of the conveyor D toreceiveone end of asupport tube 27. The split upper end portion 47 of the upright has aclamping screw extending across the longitudinal slit thereof androtatable by a hand wheel 34 to either loosenthe portion 47 so that thetube 27 can be longitudinally adjusted with respect thereto or to clampthe portion 47 upon the end of tube 27 received therein.

It will be apparent that the tube 27 overhangs the conveyor D and, atits free end, supports a bracket 33 which is clamped about the tube 27and includes a' depending portion having a laterally widened lower 'partprovided with spaced apart apertures slidahly'receiving ends of rods 16and 16' extending parallel to the axis of tube 27. The ends of rods 16and 16' remote from bracket 33 are fixedly connected to a head or cover29 provided at one end of a cylinder 20 which has its axis arrangedparallel to that of the tube 27, while the opposite end of cylinder 20is provided with a mounting portion having a dovetail, or othersimilarly shaped groove slidably receiving a projection of correspondingcross-sectional shape depending from the tubular portion 47 at theftopof upright 28 so that the cylinder 20, as well as the tube 27 can belongitudinally adjusted with respect to the upright 28.. The mountingportion of cylinder 20 may be further provided with suitable set screwsengageable with the part of tubular portion 47 slidably received in't'hegroove of the cylinder in order to lock the latter in an adjustedposition with respect to the upright 28.

A piston 11 is axially movable within cylinder 20 and carries sealingrings 13 which are held on the piston by collars 12 or the like so thatthe leakage of fluid under pressure past the piston 11 will beminimized.

A piston rod 7 extends axially from piston 11 through the cylinder head29 and, at its free end, carries a pivot pin 14 (Fig. 3) which, at itsopposite ends, is supported by sleeves 15 and 15' slidable on rods 16and 16', respectively. Coil springs 17 are provided on the rods 16 and16' adjacent the bracket 3-3 and the cylinder, head 29 so that, at theopposite ends of the operation stroke of the piston 11 within cylinder20, sleeves 15 and 15 abut against the springs 17 which therebyresiliently cushion the deceleration of piston 11 at the opposite endsof its operation stroke. 1

A lever 8 is provided with a forkedupper end portion 32 (Figs. 1 and 3)which is pivoted on the pin 14, and the lever 8 is further formed with alongitudinally extending slot 37 opening at the opposite side faces ofthe lever to slidably receive bolts which extend laterally from a leverextension 31 which is arranged at one side of lever 8. The slot 37 andthe bolts slidably received there in serve to maintain the extension 31in longitudinal alignment with lever 8 during the longitudinaladjustment of the extension relative to the lever. In 'order to hold thelever 31 in a selected longitudinally adjusted spasms positionrelative-to lever '8, the upper end of extension 31 is provided with alaterally directed flange which overlies the top surface of lever 8 andwhich is formed with a tooth 38 engageable in a selected one of a seriesofspaced apart notches 36 formed in the top surface of lever 8. Further,the flange 30 of extension 31 may be provided with a longitudinalslotreceiving suitable bolts which can be screwed into tapped bores formedin the top surface of lever 8 intermediate the notches 36 in order toclamp the extension 31 in its adjusted position relative to lever 8.

The lower end of lever extension 3i has a bent arm 49 extendingtherefrom, and a smoothing roller 4, which preferably has a contouredresilient surface for accommodating itself to the shape of the boot onthe last K, is rotatably journaled between bent arm 49 and the free end,of lever extension 31.

Coil springs 10 and 10' are connected, at one end, to a laterallyextending anchor rod 39 (Figs. 1 and 2) -which is suitably secured tothe flange 30 of lever extension 31 and, at their other ends, to ananchor rod which extends laterally with respect to the axis of pistonrod 7 and which is supported by an arm or holder 41 depending frompiston rod 7 and fixedly secured on the latter. The springs 10 and 10urge the lever 8 and its extension 31 to swing about pivot pin 14 in thedirection moving roller 4 downwardly toward a boot 1 J v positioned on alast K which is located at the station occupied by the upright 28 whilethe conveyor D is at rest.

In order to maintain the roller 4 in a raised, inoperative positionduring the intermittent movements of the conveyor D, the deviceembodying the invention further includes a bent arm'35, which, at itsupper end, is secured to the head 29 of cylinder 20 and, at its lowerend, has a forked portion 48 rotatably carrying an abutment roller 9positioned under and in back of the inclined lever 8. Thus, when thepiston 11 is displaced within cylinder 20 in the direction towardupright 28, that is, in. the direction for retracting the piston rod'7,the inclined lever 8 depending from the pivot pin 14 is moved againstthe abutment roller 9 which is in a fixed position relative to thecylinder 20 so that the abutment roller 9 then acts to swing the lever 8and its extension 31 in the upward direction, against the action of thesprings 10 and 10', for displacing roller 4 to the desired raised,inoperative position.. On the other hand, when piston 11 is moved in thedirection away from upright 28, thatis in the direction extending pistonrod 7 from cylinder 20, lever 8 is correspondingly bodily displaced awayfrom abutment roller 9 so that the springs 10 and 10 are then free todraw or urge lever 8 and its extension 31', and hence also roller 4, inthe downward direction.

In accordance withthe invention, when the conveyor D is brought to restwith one of its lasts K carried by a carriage 3 and supporting a boot 1located at the position of the upright 28, and a strip 2 is applied overthe rear seam of the boot, fluid under pressure, which may be, eithercompressed air or a hydraulic liquid, is supplied alternately to theopposite ends of the cylinder 20 in order to effect reciprocation ofpiston 11 within cylin- 'der 20 so that roller 4 is made to roll alongstrip 2 with a yieldable pressure resulting from the action of the sp in1 n In order to control thesupplying of fluid under pressure to cylinder20, the device embodying the invention further includes a suitableshaped radial cam 5 fixed on a cam shaft 6 which is rotatably journaledin the'frame R of the conveyor and which isdriven for a predeterminednumber of revolutions by an electric motor (not shown) following theactuation of a push-button switch (not shown) by the operator of thedevice. The periphery of carn 5 is engaged by a cam follower roller 42which is rotatably supported at the end of a pivoted lever 43. Lever 43is pivotally connected, intermediate its ends, to a link 19 which is, inturn, pivotally connected to a control lever 44 which operates an inletvalve 18 and an outlet valve 23 provided at the upper and lower parts ofa control cylinder 26 having a piston (not shown) movable therein; Theupper end of control cylinder 26 is connected to the back end ofcylinder 20 by a feed conduit or pipe 24 opening into cylinder 20through a metering valve 25, while the lower end of control cylinder26and the forward end of cylinder 20 are interconnected by an outlet pipeor conduit 46 which is also connected to a pipe line 21 containing asupply of fluid under pressure.

When the cam shaft 6 is rotated, cam 5 rocks the lever 43 to causecorresponding rocking of the lever 44 so that the control cylinder 26serves first to supply fluid under pressure to the back end of cylinder20 for causing forward movement of piston rod 7, and then to supplyfluid under pressure to the forward end of cylinder 20 for effectingbackward movement of piston rod 7 during each revolution of the camshaft.

The apparatus described above operates as follows:

A boot 1 is placed upon each ofthe lasts K supported by a carriage 3 ofthe conveyor D during a period when the latter is at rest and, at thesame time, the strip 2 is laid over the back seam of the boot whichfaces upwardly on the last.

, During each intermittent movement of the conveyor D, the cam shaft 6is at rest and disposed so that the cam 5 causes the control cylinder 26to supply fluid under pressure to the forward end of cylinder 20,whereby piston rod 7 is retracted or drawn rearwardly in order to engagethe pivoted lever 8 with the abutment roller 9 and thereby raise roller4 to its inoperative position. At the end of each intermittent movementof conveyor D, a last K, with a' boot 1 thereon, comes to rest at thesta tion or location of the upright 28 so that the boot 1 then underliesthe raised roller 4. The operator at such station or location thenactuates the control for the motor (not shown) driving cam shaft 6 sothat the latter is automatically rotated for a predetermined number ofrevolutions,,and this rotation, as previously described, causes thesupplying of fluid under pressure to cylinder 20 in a manner to effectthe repeated reciprocation of piston 11 within cylinder 20. During suchrepeated reciprocation, the lever 8 moves bodily in the forward andrearward direction and, when disengaged from abutment roller 9, thesprings 10 and 10' act resiliently upon lever 8 to urge roller 4 intorolling contact with the strip 2 applied to the back seam of the boot.Thus, roller 4 is repeatedly moved along the strip 2 in order to smooththe latter against the leg portion of the boot and thereby ensure theadherence of the strip to the boot.

When rotation of cam shaft 6 is completed, cam 5 returns to its normalor inoperative position in which fluid under pressure is supplied to theforward end of cylinder 20 thereby to draw piston rod 7 in the rearwarddirection for again engaging lever 8 with abutment roller 9 for raisingroller 4 to its inoperative position. With the roller 4 returned to itsinoperative position, the conveyor D again effects an intermittentmovement to bring another last K with a boot 1 thereon into positionunder the roller 4. When the conveyor D is again at rest, the operatoronce more causes rotation of the shaft 6 in order to repeat the actionof the smoothing roller 4 upon the strip 2 of the boot 1 then located atthe station occupied by the device embodying this invention.

When additional finishing operations are performed on the successiveboots at locations along the conveyor D following the station occupiedby the device embodying this invention, the finished boots are strippedfrom the lasts so that the latter can again receive boots which are tobe subjected to the smoothing action of the roller 4.

It will be apparent from the above that the device embodying the presentinvention serves to smooth the strip 2 laid over the back seam of eachboot 1 in order to ensure the adherence of the strip to the boot, andthat this operation is performed without requiring the tiresome manualprocedures previously employed, as described herein. Further, the deviceembodying the invention serves to improve the uniformity of thesmoothing of the strip 2 against the leg portion of the boot 1 andthereby improves the quality of the product, while permitting asubstantial increase in the rate of production.

Although an illustrative embodiment of the invention has beendescribedin detail herein with reference to the accompanying drawings,it is to be understood that the invention is not limited to that preciseembodiment, and that various changes and modifications may be effectedtherein without departing from the scope or spirit of the invention,except as defined in the appended claims.

We claim:

1. A device for smoothing a connecting strip which is laid over the backseam extending along the leg portion of a rubber boot, comprising a lastfor supporting the boot with the leg portion of the latter extendinghorizontally and having its back seam along the top thereof, an uprighthaving a support tube extending horizontally from the upper end thereofand overlying said last with the axis of said tube being generallyparallel to the axis of the leg portion of the boot on said last, a pairof laterally spaced apart guide rods extending parallelto said tubebelow the latter, a pivot pin extending between said guide rods, meansslidably mounting said pivot pin on said guide rods for movement alongthe latter, a longitudinally adjustable lever assembly pivoted, at oneend, on said pivot pin and inclined downwardly from the latter, apressure roller rotatably mounted at the other end of said leverassembly with the axis of said roller extending horizontally at rightangles to said axis of the support tube so that said roller can rollalong the connecting strip of a boot on said last in response to themovement of said pivot pin along the guide rods, an actuating cylinderhaving a piston reciprocable therein and a piston rod projecting axiallyfrom the cylinder, said cylinder being arranged with its axis extendingparallel to the axis of said guide rods and disposed laterallyintermediate the latter, said piston rod being connected to said pivotpin to displace the latter along said guide rods in response to themovement of said piston insaid cylinder, and means operative tosupplyfluid under pressure alternately to the opposite ends of said cylinderto cause reciprocation of said piston and corresponding movement of saidroller back-and forth along a'connecting strip laid over the back seamof a boot on said last.

upright and having a head at its other end; and wherein said guide rodsare mounted, at their opposite ends, in said bracket depending from saidtube and in said head of the actuating cylinder.

3. A device as in claim 2; furthercomprising spring means connectedbetween said lever assembly and said piston rod to urge said leverassembly to pivot in the direction moving said pressure rollerdownwardly against said last.

4. A device as in claim 3; wherein said spring means includes a pair ofhelical tension springs arranged at opposite sides of said leverassembly, a lateral rod fixed to said lever assembly and having saidsprings anchored to its opposite ends, a bracket depending from saidpiston rod, and a lateral rod carried by the last mentioned bracket andhaving said springs anchored to its opposite ends.

5. A device as in claim 1; wherein said lever assembly includes twoelongated parts relatively movable parallel to each other to vary thelength of said lever assembly,

and means releasably securing said parts to each other in a selectedlongitudinally adjusted position.

6. A device as in claim 1; further comprising an abutment member fixedlymounted in relation to said guide rods and engaged by said leverassembly as said piston nears one of its extreme positions in saidcylinder to pivot said lever assembly in the direction raising saidroller relative to said last.

7. A device as in claim 6; further comprising an intermittently movedconveyor carrying said last for movement of the latter to and away froma location under said support tube; and wherein said piston ismaintained at said one extreme position during movement of saidconveyor.

References Cited in the file of this patent UNITED STATES PATENTS231,707 Gilmore Aug. 31, 1880 344,650 Gilmore June 29, 1886 523,285 Juddet al. July 17, 1894 610,314 Winkley Sept. 6, 1898 939,621 Parker et alNov. 9, 1909 1,097,845 Colt May 26, 1914 1,218,983 Clark Mar. 13, 19171,239,664 Baxter Sept. 11, 1917 2,063,919 Fredericksen Dec. 15, 19362,088,921 Polleys Aug. 3, 1937 2,439,889 Hart et al Apr. 20, 1948FOREIGN PATENTS 663,916 Germany Aug. 18,- 1892 665,328 Great BritainIan. 23, 1952

